Means for scoring sheet workpieces



Aug. 18, 1964 B. P. LOKEY MEANS FOR SCORING SHEET WORKPIECES 4 Sheets-Sheet 1 Filed May 21, 1962 INVENTOR. flue/r5 F 10 ATTORNEYS .Aug. 18,1964

P. LOKEY I MEANS FOR SCORING SHEET WORKPIECES Filed May 21, 1962 4 Sheets-Sheet 3 INVENTOR.

kEwSMSQ kzww 602A?- 2. 1 a/rsv u 9 G W Aug. 18, 1964 B. P. LOKEY I 3,144,314

MEANS FOR SCORING SHEET WORKPIECES Filed May 21, 1962 I 4 Shets-Sheet 4 I INVENTOR. 7 50 m; ZOAEV' BY ,4 TroRA E'rs United States Patent 3,144,814 MEANS FOR SCORING SHEET WQRKPKEQES Burke P. Lokey, (Iovington, Va., assignor to St. Regis Paper Company, New York, N.Y., a corporation of New York Filed May 21, 1962, Ser. No. 196,204 4- Claims. ((31. 93-3) This invention relates to apparatus for scoring Workpieces of sheet material, and more particularly to apparatus for forming score lines in and transversely of a suc cession of bag tubes of paper or the like sheet material wherein the speed and phase relationship between the moving bag tubes and the moving scoring means are controlled by novel means.

This invention comprises an improvement upon the scoring apparatus disclosed in the US. patent to E. E. Burroughs No. 2,837,012, granted June 3, 1958, and such disclosure is herein incorporated by reference.

In the aforementioned patent the following statement is quoted for the purpose of illustrating the distinctions of the present invention thereover:

The invention in one aspect is constituted by the following combination: Conveyor means are provided for conveying a succession of bag tubes along a common path and at a common interval. Such conveyor means moves the bag tubes successively along a common, preferably horizontal, plane and successively past a bag tube scoring station. At such scoring station there is situated a pair of score bars which are respectively provided with a groove and a score blade and which are brought together periodically in close parallel relationship thereby successively to press each bag therebetween and to form a score line transversely thereof extending in a direction parallel to the direction of the conveyor. Each of said score bars is mounted upon a pair of substantially parallel rotatable cranks, each score bar thereby comprising a connecting rod of a parallel crank four-bar linkage. The rotatable cranks of each of such linkages are operatively interconnected to bring the score bars into bag tube scoring cooperation, once for each revolution of a crank. The region of each bag which is to be scored normally moves in the aforementioned plane along its path of movement and such plane is referred to as the scoring plane. In order to maintain the desired phase relationship between the score bars and the oncoming bag tubes and at the same time to bring the linear speed of score bars into synchronism with the linear speed of the conveyor and hence the bag tubes, I have found it desirable cyclically to vary the angular speed of the cranks of said four-bar linkages by any suitable means whereby the score bars are increased in linear velocity as they approach each moving bag tube and reach maximum linear speed during the pressing of the tube therebetween, such maximum linear speed being synchronized with the linear speed of the conveyor, and hence of the bags.

For the purpose of maintaining the aforementioned phase relationship there were employed means for rotating in timed relationship the cranks of the parallel equal crank four-bar linkages which included means for cyclically varying the angular speed thereof as a function of the differential between the radius of the cranks and the dimension measured from the axis of rotation of such cranks to the plane of the scoring region perpendicular thereto, such radius being less than such dimension for reasons stated in the description of the aforementioned patent. At the time of filing the application for the patent aforementioned, it was felt that the purpose of such cyclical variaion of the angular speed was to bring the linear velocity of the score bars into exact synchronism (equality) with the linear velocity of the conveyor means durice ing the scoring cooperation of the score bars. The conveyor means and parallel equal crank four-bar linkages in such disclosure were operatively interconnected thereby to bring the cycle of bag movement by the conveyor means into phase with the cycle of score bar movement whereby the bag tubes were scored in succession at the scoring station.

The aforementioned means for cyclically varying the speed of the linkages has proven unnecessarily expensive.

Such relationship of the two speeds during scoring was heretofore believed essential because it was thought that if the score bars moved either too fast or too slow during scoring, they would dislodge the bag tube blanks from their bag clamps which, via the conveyor, pulled same by their leading edges.

The aforementioned differential in length between such crank radius and such other dimension above described led to the view that there was only one way to solve the problem, namely, such cyclical variation of score bar speed.

I have found that I can accomplish the advantage of eliminating the expensive and complicated means for cyclically varying the score bar speed heretofore thought necessary, and at the same time meet the requirement for synchronized score bar and conveyor (or bag tube) cycles, while achieving the further advantage of avoiding any dislodging or misalignment of the bag tubes.

One of the objects of the present invention is to provide novel apparatus for performing the same scoring function as the apparatus disclosed in such patent but eliminating such expensive means for cyclically varying the angular speed of the linkages.

Accordingly, the present invention, in one of the aspects thereof, comprises: a conveyor for conveying a succession of bag tubes along a common path and at a selected frequency with respect to a norm point; means for scoring each of said bag tubes in succession as each passes a scoring station, such means comprising a pair of score bars or elements between which each tube is pressed, one of such score elements having a score blade positioned for bag tube scoring cooperation with a correspondingly shaped groove formed in the other element; a pair of parallel equal crank four-bar linkages for mounting respective of said score elements for parallel reciprocative motion, each such score element comprising a connecting bar of its respective linkage, such connecting bar extending along such path, said parallel equal crank linkages being constructed and arranged for moving said score elements in selected phase relationship whereby such score blade is pressed into such groove with a bag tube therebetween at such scoring station; and means for driving said conveyor means and said equal crank four-bar linkages whereby the crank arms thereof are driven at a constant angular velocity of one cycle of the crank arm shafts for each single tube that passes such scoring station, the radius of each of said crank arms being selected whereby said score elements are moved, whereby the horizontal velocity component thereof is substantially equal to or slightly greater than that of the bag tube during the contact of such elements and tube, for example, substantially equal at the points of first and last contact before and after tube scoring, but during approach to a position half way between such points said horizontal component gradually increases to a peak value, and

gradually diminishes thereafter.

The above and further objects and novel features will more fully appear from the description set forth below when read in connection with the accompanying drawings, it being understood that the latter do not constitute a definition of the limits of the invention, reference for this latter purpose. being had to the appended claims.

In the drawings:

FIG. 1 is a perspective view illustrating schematically one form of apparatus embodying the present invention;

FIG. 2 is a further schematic illustration of a pair of linkages employed for mounting and moving the scoring means of the present invention, and including a showing of one form of gear train comprising a portion of an operative interconnection between a source of driving torque and such linkages;

FIG. 3 is a side elevation of certain portions of the apparatus shown in FIG. 1 but in a different operating position;

FIG. 4-is a graphical representation of the travel of the workpieces plotted against the horizontal velocity component of the scoring bars employed in this apparatus;

FIG. 4a is an enlarged view of a portion of FIG. 4;

FIG. 5 is a view, partly in section and with parts broken away, taken transversely of the parallel scoring bars during scoring cooperation therebetween and showing in cross-section the gear train schematically illustrated in FIG. 2; and

FIG. 6 is a side elevation of a scoring unit employed in the present invention and also a slitting unit for forming the end slits in the bag tube blanks.

Referring to the drawings in greater detail with particular reference to FIGS. 1, 2 and 3, the novel apparatus is shown in an environment for forming score lines upon fiat sheet'like workpieces, such as bag tubes or bag tube blanks prior to forming the bottoms thereof, the score lines extending in the direction of motion of the conveyor which moves such bag tube blanks. Such score lines are desirable in certain types of bag bottom forming devices for the purpose of preforming a line about which the opposite end portions of the bag tube can be bent at 90 to the plane of the main body of the bag, as shown in FIG. 1. The ends of the bag tubes so bent thereafter are operated upon by other devices not shown for forming the bag bottoms.

In FIG. 1, a conveyor 10 is provided for conveying a succession of bag tubes along a common path and at a uniform selected interval y (FIG. 3). Two of such bag tubes are shown illustratively at 11 and 12 (FIG. 1). The conveyor 10 preferably comprises a pair of parrallel endless sprocket chains 13 and 14 which, at their opposite extremities, respectively pass over sprocket wheels 15, 16 and 17, 18. A plurality of cooperating pairs of bag tube clamps are positioned on said chains 13 and 14, for example, a clamp 19 on chain 13 cooperates with a clamp 20 on chain 14 for clamping and pulling the bag tube blank 11 in the direction of arrow 21. on chain 13 cooperates with a clamp 23 on chain 14 for the same purpose for bag tube 12. The interval between the two pairs of clamps 19, 20 and 22, 23, as aforementioned, is indicated by the distance or interval y (FIG. 3) and is common between all of such pairs of clamps as measured along the length of the chains. Other pairs of bag clamps, such as 24 and 25, are also provided spaced at such common interval. The sprocket wheels 15, 16 and 17, 18 are driven together preferably by rigidly interconnecting the driving shafts thereof or by employing a common driving shaft for such sprocket wheels, as indicated at 25a.

The aforementioned bending of the bag tube blanks is accomplished by any suitable means, such as being strips 26, which cooperate with a strip 27 (FIG. 1). The bag tubes, such as 11 and 12, are supported by suitable flooring, such as 11a (FIG. 5) which may extend the length of the conveyor 10, and which is formed with slots to accommodate the chains 13 and 14 and also for accommodating the scoring apparatus.

The folding of the end portions, such as 1201 and 12b of the bag tube 12, is thus facilitated by preliminarily forming the main score lines transversely near each of the ends of the bag tube. Such score lines are indicated at 28 and 29 on the bag tube blank 12.

And a clamp 22' Referring to the bag tube 11, the proposed location of the score lines which correspond to lines 28 and 29 on bag 12 are shown by broken lines 30 and 31.

The scoring device for making such score lines in succession is described as follows: Only one such scoring device is to be described, it being generally indicated at 32 and it being understood that on the opposite side of the conveyor an analogous scoring device is employed.

A pair of straight score bars 33 and 34 are employed in the scoring device 32 for forming a score line along the broken line 30. Such score bars 33 and 34 are well shown in cross-section in FIG. 5 and comprise respectively an elongated element including a score blade 35 which is held by the bar 33 for periodic scoring cooperation with a mating groove 36 formed along the upper face of the score bar 34. The term score line as employed herein refers to a line or groove about which the paper can be bent easily.

The elongated score bars 33 and 34, in the form shown, extend in a direction parallel to the direction of motion of the conveyor 10 (but the invention is not so limited) and are so moved in the present invention that, when in contact with a bag tube they are proceeding in the same direction but at a slightly greater speed as will appear below. The score bars 33 and 34 are moved in true parallel relationship into scoring cooperation with the end of the bag therebetween. The means for so moving the score bars comprise a pair of parallel equal crank four-bar linkages well illustrated schematically in FIG. 2, the score bars 33 and 34 comprising respectively the connecting rods of their linkages. The uppermost of such parallel equal crank four-bar linkages comprises such score bar 33 which is the connecting rod for this linkage,

the latter further including a pair of cranks or crank arms 37 and 38 which are mounted upon suitable shafts 37a and 38a (FIGS. 2 and 3). The score bar 33 is also represented in FIG. 2 by the bar AB, the cranks 37 and 38 respectively by the bars AC and BD. The line of centers of such linkage is designated CD. The latter line is fixed and corresponds to the distance between the axes of rotation of the shafts 37a, 38a and thus of the cranks 37 and 38.

Analogous cranks 41 and 42 are employed for mounting the lower score bar 34, the linkage of which is analogous to that above described.

The upper and lower of such linkages are respectively designated in FIG. 1 by the numerals 43 and 44.

Such linkages 43 and 44 are geared to move together by any suitable means. For example, one or both of the shafts 37a, 380 are caused to rotate with shafts 41a, 42a of linkage 44 by toothed gearing, such shafts 41a, 42a (FIG. 3) respectively mounting the cranks 41 and 42.

Referring again to FIG. 2, the score bar 34 comprises the connecting rod EF of the lower four-bar linkage, the line of centers thereof being indicated by GH and the respective cranks 41 and 42 by EG and PB.

The power means for driving the conveyor 10 comprises an electrical motor 45 which is drivably connected to the shaft 25a of the sprocket wheels 15 and 17 by the means schematically shown at 2511 in FIG. 1, and which drives the sprocket at a speed proportional to the motor speed.

The linkages 43 and 44 are also driven by the electric motor 45 at a speed proportional to the motor speed as discussed below, thereby facilitating the maintenance of a desired phase relationship between the motion of such linkages and the motion of the conveyor 10, although the invention is not necessarily limited to such common power source.

The score bars 33 and 34 are brought together in scoring cooperation (FIG. 3) wherein the leading edge of a bag tube, such as 11, is in alignment substantially with the leading edges of the score bars 33 and 34. By adjusting the linkages 43 and 44 to bring the leading edges of both the bag and the score bars into such register, as

shown in FIG. 3, it is possible to score all widths of bag tubes without special adjustment therefor and up to the limit of the length of the score bars.

In order that a proper phase relationship shall exist between the movement of the score bars 33 and 34 and the movement of the conveyor 10, and hence the bag tubes, such as 11 and 12, there should be one complete cycle of movement of the score bars for each complete cycle of movement of a bag tube with respect to a norm or reference point at the scoring station.

In maintaining such relationship of cycles, that is, in maintaining the same frequency of score bar cycles and bag movement cycles, the factors to be considered are:

(a) The radius of the cranks of the linkages 43 and 44, representative of which is the radius 46 of the crank 42 (FIG. 6), which radius is measured between shaft center 4217 and supporting stud center 42c;

(b) The perpendicular distance between 42b, the axis of rotation of the shaft 42a, and the plane of the bag tube 11, such plane being coincident with the plane of the scoring region. Such distance is indicated by the dimension 47 (FIG. 6) which is greater than the aforementioned crank radius 46;

(c) The common interval y between the bag tube clamps;

(d) The linear speed of the score bars relative to the linear speed of the conveyor during the time the score,

bars are in contact with the bag tube.

In the past, as aforementioned, it has been thought necessary to employ a cyclical variation in the angular speed of the cranks of the linkages 43 and 44.

This was because of the selection of the radius 46 to be less than the dimension 47 (FIG. 6) and this was done in order to avoid interference with the score blade 35 and with the groove 36 by studs 33a and 34a (FIG. 5) which interconnect pivotally each of the cranks with their respective score bars. The radius 46 cannot be exactly equal to the dimension 47 without damage to the bag tube or detriment to the apparatus.

However, I have now found that it is not necessary so to vary cyclically the speed of the linkages 43 and 44.

The crank arms of the linkages 43, 44 in the present invention are driven by an ordinary train of circular gears as shown in FIG. 2 at 48, 49 and 52-55, inc., to give a constant angular velocity (Vx) substantially equal to slightly greater than that of the workpiece or bag tube while the bars are in contact therewith as represented between points 4312 and 43c (FIG. 4).

Consequently, the angular speed of the cranks of each of the linkages 43, 44 is under the influence of the gear train of FIG. 2, illustratively, consisting of an ordinary circular spur gear 48, operatively connected to the motor 45, as indicated at 25b, FIG. 1, and which meshes with an ordinary circular spur gear 49, both having axes of rotation 50 and 51, respectively. The spur gear 49 is in mesh with spur circular gears 52 and 53, respectively, FIG. 2, which are rigidly secured to the aforementioned shafts 41a and 42a.

Preferably the spur gears 52 and 53, FIG. 2, are respectively in mesh with two other spur gears 54 and 55 which in turn respectively are rigidly secured to the shafts 37a and 38a for driving the cranks 37 and 38.

By employing the above structure, it is possible to eliminate the expensive means for effecting a cyclical variation of the score bars, for example, costly elliptical gearmg.

There will now be set forth one example of calculations employed for designing apparatus for carrying out the objectives of the invention.

In order to achieve the aforementioned horizontal velocity component of the score bars which is slightly greater than that of the bag tubes (or paper) While the bars are in contact with such tubes, the following is assumed by way of illustration:

(1) The scoring bars must have 'a horizontal velocity component Vx equal to 28 inches per bag tube which comprises the bag tube or paper speed at or before the instant the bars contact the bag tubes.

(2) The scoring bars 33 and 34 contact the bag tubes, such as 11, while such bars are, for example, A inch apart. This is the point where the knives of the slitting unit 56 (FIG. 6) contact the bags and the calculations below are based on this figure. Unit 56 makes slits 56a (FIG. 3).

The radius of the crank arms, such as radius 47 of the crank arm 42, is selected, and the characteristics of the gear train are further selected to meet the above conditions as follows:

Let

Referring to FIG. 2, it is apparent that:

(11) Vt=21rR in./rev.=21rR in./bag

and

(12) Vx:Vt cos 6.

substituting (13) Vx=21rR cos 0 but cos 0= therefore 15 V$=2TR.( =21r(R Y) solving for R from items 1 and 5 (l7) Vx=Vp=28 in./bag

from item 2 6 (18) Y= in then 28 (19) R= +}s=4.456+.125=4.581 1n.

Dc (20) =3 from drive of machine.

Then the crank arm gear (e.g. 52-55) and drive gear 48 are selected as follows:

Crank arm gear:

Pitch=6 Teeth=69 (21) Dc=pitch dia.=11.1500

Drive gear:

Pitch=6 Teeth=23 (22) Dd=pitch diameter=3.833

Then

De 11.500 (23) Fa 3.833

This agrees with item 20.

It is-apparent from the assumptions (items) 1 and 2, that the scoring bars are always traveling faster than paper speedwhile they are in contact with the tubes. The difference in the travel of the scoring bars and the tube is determined as follows:

Lx=travel of 'bar while in contact with tube.

(28)- Lx=2R'sin 0=2X4.58l sin 13:2.06O in. Lp=travel of tube while in contact with bars.

Then the overtravel of the bars will be:

(30) Lx-Lp=2.060-2.020=.040 in.

This overtravel is about the same that occurs with respect to the slitting unit 56'. The score bars thus push the tubes into the grippers or clamps, e.g. 19, 20. The overtravel is less on the bottom scoring units because 0 is much less than 13 when the bars contact the tubes.

From item 13, any desired horizontal velocity of the scoring bars can be attained by selection of the radius of the crank arms.

In FIGS. 4 and 4a, curve 43a, as aforementioned, is a graphical representation of Vx plotted against workpiece travel in inches per revolution of the score bar crank, in apparatus embodying the present invention. For purposes of illustration only, the radius R, as in item 19 above, is 4.581 inches, or a diameter of 9.162 inches. For purposes of comparison, a curve 57 also is shown in FIG. 4a of Vx plotted against workpiece travel for a slitter knife such as 58 of the unit 56 (FIG. 6) which knife is cyclically varied in angular velocity by elliptical gears interposed in the drive thereof and wherein the dimension equivalent to R is 3.5 inches.

Reverting to FIG. 4a, there is shown on an enlarged scale the relationship of curves 43a and 57 of FIG. 4 at the peak thereof with particular reference to the points 43b and 43c. The latter two points represent the contact of the score bars or scoring elements with the paper during a typical single cycle. It will be noted that the horizontal distance between the points 43b and 430 onthe curve 43a is slightly greater than the horizontal distance between points 57a and 57b on the curve 57. Dimension 61 of FIG. 411 represents the difference between the maximum value of the horizontal component Vx of a crank, such as 42, in comparison to the workpiece movement which is represented by the line 28Tas shown in the lefthand margin of the graph of FIG. 4a. Such maximum value Vx occurs when the crank 42 is in the position shown in FIG. 3.

Dimension 62 of FIG. 4a represents the difference between the maximum value Vx of a slitter knife, such as 58, and the speed of the workpiece. Dimension 61, representing operation of the present invention, is less than the dimension 62 thereby indicating that the present invention embodying the normal spur gear type of drive with uniform angular speed of the crank is required to reach a lesser maximum Vx than a cyclically operated mechanism such as the slitter 58 whose speed is varied by elliptical gears as aforementioned.

FIG. 4a clearly indicates by the curve 43a the characteristic of the present invention which embodies the means for driving the conveyor means and the four-bar linkages whereby the crank arms of the latter are driven at a constant angular velocity of one cycle of the crank arm shafts for each single tube that passes the scoring station, the radius of each of such crank arms being selected whereby the score elements are moved, whereby the horizontal velocity component thereof is substantially equal to or slightly greater than that of the bag tube during the contact of suchelements and tube, for example, substantially equal to the points of first and last contact before and after tube scoring, but during approach to a position halfwaybetween such points said horizontal component gradually increases to peak value and gradually diminishes thereafter.

In a separate embodiment of the invention, the two slits 56a in the bag tube (FIG. 1) instead of being made by the slitting unit 56 of FIG. 6, can be made by a slitting unit embodying the present invention but substituting slitter knives for the score bars. This is accomplished, in one form, by employing in a slitting unit a pair of double crank four-bar linkages as in such FIG. 6 but modified by eliminating the score bar 35 and groove 36 (FIG. 5) and substituting a pair of slitter knives, for example, mounted on the top score bar 33 and spaced by a dimension equal to the spacing between the two'slits 56a (FIG. 1). Such slitter knives can coact with a pair of cooperating slitter grooves formed in or mounted on the lowermost bar 34. Such-slitter knives and grooves are thus analogous in purpose to the single slitter knife 58 and groove 58:: of the slitting unit 56 (FIG. 6).

Also, in other and separate embodiments of the invention, there may be mounted upon such pair of parallel equal crank four-bar linkages other tools for acting on the bag blanks, for example, other scoring tools for forming score lines which are angularly disposed with respect to the score line 31 (FIG. 1). Also, slits in other attitudes and locations can be formed in the bag tubes by appropriately rearranging the knives and grooves.

This application is a continuation-in-part of my copending application Serial No. 861,024, filed December 21, 1959, and now abandoned.

What is claimed is:

1. Bag scoring apparatus comprising: a substantially horizontally disposed endless conveyor passing about oppositely disposed rolls for conveying bag tubes successively past scoring means, said conveyor being provided with upstanding bag clamps equi-spaced therealong adapted upon engagement by said bag tubes to position the same in proper scoring alignment with said scoring means, said means including pairs of parallel shafts disposed respectively above and below and normal to the travel path of said conveyor, male and female scoring bars eccentrically mounted on said shaft pairs respectively, for reciprocative movement and intermittent mating engagement of said scoring bars upon concurrent rotationof said shafts at a common angular velocity, said scoring bar mounting means including parallel equal crank linkages, means for driving said shafts and conveyor rolls in fixed angular relation to one another, comprisinga motor and shafts and circular gears connecting said linkages and roll shafts to said motor, said gears being constructed and arranged to rotate the cranks of said linkages at a constant angular velocity and so proportioned in relation to said roll diameters and scoring bar cranks to move said bars while in mating engagement at a lineal speed slightly exceeding the lineal speed of said conveyor, and such as to move the successive bag tubes into positioning engagement with said conveyor clamps, respectively, and to score said tubes as thus positioned.

2. Bag scoring apparatus comprising: a substantially horizontally disposed endless conveyor consisting of spaced chains passing, respectively, about oppositely disposed sprockets, for conveying bag tubes successively past scoring means, said conveyor chains being provided with upstanding bag clamps equi-spaced therealong adapted upon engagement by said bag tubes to position the same in proper scoring alignment with said scoring means, said means including pairs of parallel shafts disposed respectively above and below and normal to the travel path of said conveyor, male and female scoring bars eccentrically mounted on said shaft pairs respectively, for reciprocative movement and intermittent mating engagement of said scoring bars upon concurrent rotation of said shafts at a common angular velocity, said scoring bar mounting means including parallel equal-crank linkages, means for driving said shafts and conveyor sprockets in fixed angular relation to one another, comprising a motor and shafts and circular gears linking said sprockets and roll shafts to said motor, said gears being constructed and arranged to rotate the cranks of said linkages at a constant angular velocity and so proportioned in relation to said roll diameters and scoring bar cranks to move said bars While in mating engagement at a lineal speed slightly exceeding the lineal speed of said conveyor, and such as to move the successive bag tubes into positioning engagement with said conveyor clamps, respectively, and to score said tubes as thus positioned.

3. Bag scoring apparatus comprising: a substantially horizontally disposed endless conveyor passing about oppositely disposed rolls for conveying substantially rectangular bag tubes successively past scoring means, said conveyor being provided with upstanding bag clamps equi-spaced therealong adapted upon engagement by said bag tubes to position the same with opposed edges thereof parallel to the direction of conveyance and in proper scoring alignment with said scoring means, said means including pairs of parallel shafts disposed respectively above and below and normal to the travel path of said conveyor, male and female scoring bars eccentrically mounted on said shaft pairs respectively, for reciprocative movement and intermittent mating engagement of said scoring bars upon concurrent rotation of said shafts at a common angular velocity, said scoring bar mounting means including parallel equal-crank linkages, means for driving said shafts and conveyor rolls in fixed angular relation to one another, comprising a motor and shafts and circular gears connecting said linkages and roll shafts to said motor, said gears being constructed and arranged to rotate the cranks of said linkages at a constant angular velocity and so proportioned in relation to said roll diameters and scoring bar cranks to move said bars while in mating engagement at a lineal speed slightly exceeding the lineal speed of said conveyor and such as to move the successive bag tubes into positioning engagement with said conveyor stops, respectively, and to score said tubes as thus positioned.

4. Bag scoring apparatus comprising: a substantially horizontally disposed endless conveyor passing about oppositely disposed rolls for conveying bag tubes successively past scoring means, said conveyor being provided with upstanding bag clamps, equi-spaced therealong adapted upon engagement by said bag tubes to position the same in proper scoring alignment with said scoring means, said scoring means including pairs of parallel shafts disposed respectively above and below and normal to the travel path of said conveyor, male and female scoring bars, parallel equal-crank linkages eccentrically mounting said bars on said shaft pairs respectively, for reciprocative movement and intermittent mating engagement of said scoring bars upon concurrent rotation of said shafts at a common angular velocity, means for driving said shafts and conveyor rolls in fixed angular relation to one another, comprising a motor and shafts and circular gears connecting said linkages and roll shafts to said motor, said circular gears being operative to rotate the cranks of said linkages at a constant angular velocity of one cycle of said parallel shafts and said score bars for each bag tube delivered on said conveyor there past.

References Cited in the file of this patent UNITED STATES PATENTS 1,882,531 Ungar Oct. 11, 1932 2,106,255 Novick Jan. 25, 1938 2,202,889 Bates June 4, 1940 2,467,879 Billeb Apr. 19, 1949 2,837,012 Burroughs June 3, 1958 2,845,849 Hahn Aug. 5, 1958 

1. BAG SCORING APPARATUS COMPRISING: A SUBSTANTIALLY HORIZONTALLY DISPOSED ENDLESS CONVEYOR PASSING ABOUT OPPOSITELY DISPOSED ROLLS FOR CONVEYING BAG TUBES SUCCESSIVELY PAST SCORING MEANS, SAID CONVEYOR BEING PROVIDED WITH UPSTANDING BAG CLAMPS EQUI-SPACED THEREALONG ADAPTED UPON ENGAGEMENT BY SAID BAG TUBES TO POSITION THE SAME IN PROPER SCORING ALIGNMENT WITH SAID SCORING MEANS, SAID MEANS INCLUDING PAIRS OF PARALLEL SHAFTS DISPOSED RESPECTIVELY ABOVE AND BELOW AND NORMAL TO THE TRAVEL PATH OF SAID CONVEYOR, MALE AND FEMALE SCORING BARS ECCENTRICALLY MOUNTED ON SAID SHAFT PAIRS RESPECTIVELY, FOR RECIPROCATIVE MOVEMENT AND INTERMITTENT MATING ENGAGEMENT OF SAID SCORING BARS UPON CONCURRENT ROTATION OF SAID SHAFTS AT A COMMON ANGULAR VELOCITY, SAID SCORING BAR MOUNTING MEANS INCLUDING PARALLEL EQUAL CRANK LINKAGES, MEANS FOR DRIVING SAID SHAFTS AND CONVEYOR ROLLS IN FIXED ANGULAR RELATION TO ONE ANOTHER, COMPRISING A MOTOR AND SHAFTS AND CIRCULAR GEARS CONNECTING SAID LINKAGES AND ROLL SHAFTS TO SAID MOTOR, SAID GEARS BEING CONSTRUCTED AND ARRANGED TO ROTATE THE CRANKS OF SAID LINKAGES AT A CONSTANT ANGULAR VELOCITY AND SO PROPORTIONED IN RELATION TO SAID ROLL DIAMETERS AND SCORING BAR CRANKS TO MOVE SAID BARS WHILE IN MATING ENGAGEMENT AT A LINEAL SPEED SLIGHTLY EXCEEDING THE LINEAL SPEED OF SAID CONVEYOR, AND SUCH AS TO MOVE THE SUCCESSIVE BAG TUBES INTO POSITIONING ENGAGEMENT WITH SAID CONVEYOR CLAMPS, RESPECTIVELY, AND TO SCORE SAID TUBES AS THUS POSITIONED. 